Vertical oven



v. A. FOX

. VERTICAL OVEN April 11, 1950 Filed Dec. 31. 1946 Imventor nflfx f mzMWM Ottomeg 5 Patented Apr. 11, 1950 VERTICAL OVEN Vernie As Fox,Detroit, Michz; assignor, .bnmesnen assignments toYoungBrothers,-:Company, De o troit,,.Mich.,oa corporationiof Michiganq;

Application December 31, 1946; SeriaLNo'. 719L540- Thisinvention-relates to drying ovens; and in particular to verticaldrying'ovens;

One object of this invention is:.t'o provide- 2 vertical drying ovenwherein the 3111101651130 be dried are carried by an endless verticalconveyor and cooling iSifOI'CGd'iiIlllO the oven near. the unloading endof the conveyor in a direction oppositewto the direction of. motion ofthe 'con- VGYOIZJ" Another object is; to; providea -vertical dryingoven,- as-set forth in {the :precedin iobject, where in the air; withinthe ovenis heatedbya-heat exchanger: and forced upward-inadirectioncontram-Ito the'direction iofimotion' of the conveyor:

Another object is-to" provide azvertical dry.- ing oven, as set forth inthe'prelceding "objects'f, wherein a portion of the coolingair; is bledoff before'beingr heated,,by being withdrawn'from the oven throughanescape'duct or stack.

Another objectis ,to' provide a'vertical' dryiIIgoven; asset forthinlthe preceding objects; whereinmeans is providedfor recirculating theheatedair within the oven housing past theh'eat; exchanger ingsuchiamanner that much' ofthe air within: the housing is usedover and overagain, but is constantlyvadded:toby'the fresh air introduced forcooling'purposes.

Other objects and advantagesiof the invention will becomeapparent duringthe'courseof the following a description of the-accompanying;drawingS,-'Whereln:

Figure-l is' a vertical; sectionthrough a ver-- ticalrdryingoven,accordingto-a preferred form ofrthe. invention, with the conveyor insideelevaetion;

Figure;;2:is.:a transverse fragmentary vertical section taken-.alongtheline 2-.-2 in: Figure- 1i and: I

Figurer3 isa; horizontal section taken -alongthe line 3-3iinwFigure' 1,immediately above the heat exchanger.-

Referring'tozthe drawing indetail, Figures 1 and :2:show apreferredformof the vertical dry in'g oven generally designated ID as includingan' elongated vertical housing II in the formof a: hollow column havinga loading openin I2 and-arr unloadinghpening- I3 on the opposite sidesof-the housing II nearthe'bottom thereof; Mounted 'within the housing II- is an endless'conveyor, generally designated I4, for conveyin theworkpieces to be dried from the loadingstatiorr adjacent the'loadingopening: I2 to' the unload-- ing station adjacent the unloading openingI3:

The conveyor- I4 consists 1 of? endless: chains I 5i (Figure: 2) aarranged in substantiallyiparallel ver.-*

ticale'iplanesn; and? i-havingx .U -.shaped-; changers: I6.=

2 pivotallyziconnected thereto as i at" IT and carry inghorizontalshelves I8 for receiving" and con veyingi the workpieces to be driedThe" conveyor-(chains I 5 1 at the bottom of -the P oven lionsirig" I Iencircle and mesh with: spaced sprockets 59' mounted on a-horizontal 2shaft" 20 which is journaled: in :beariiig brackets "20w extending upward from' the floor 2 I at locations. outside the" ovenhou'sing I Ii'At the'itop'smf their runs;-the-' conveyor chains I5 encircle: and:mesh with; similar spacedl sp1iockets 22 (one only-being v shown):mounted on'ia shait 23 g ournaled in the opposite sidesv of the housing:II. Thel 'sha'ftf- 23i-is' dri-ven so as to rotate in the direction oi'the'solidi-arrowby' any; suitable am'e'ans ;-=suchr as',?- f0r'example; by 1 the pulley izl mounted? on the: shaftezs 1' andl -drivenby the lo'elt 25: fronr-an external l-sourc'e of power su'ehha's anelectricrmotor andmreductionv gear? unit; .The' pulley ifl ari'dbelt"25:areshown=.merely for-1 Simplicity ofi illustration,=. whereas inactual practice theishaftrwis'tpreferably driven through gearingconnected'i-thereto.

Extending:substantially fromrwthe bottom to the top 'ofs-the" conveyorvi4 and. across I the spacebetweenv the: sprockets i 9:- and "22;; is; aJ: baffle or. partition": structure; generally designatedi 6' andincluding; a lower bafiie 21 withv a transversely bentuppieriportionozli -engaging an upper bafflej 29v zhaving-ai transverselyben't'dowerportion 30 engaging the lower bafiie 21. The bafiles 2'!ancll 292 with'ztheir portionsztZB a and 39 enclose; aheatingachamber-GI having-'andntake port 32 atthe bottom and oneormoretdischarge ports 33-at the top thereon o Mounted in; the: heatingchamber 3| is" a heat exchanger 34: (Figurer l) which isrsheated: bya"heater 35; such 'as a-sgas burner; oil -burner;:steamk pipe or-electricheater.- connectedato each dis.-= charge. port 33 is the dischargei-ductiifi ofone: or "more exhaust-fame]; each having a casing 38 Withwanvintake port 39 'andl a shafti lfl" with one or more -bladed -rotors. Theshaft 40' is driven by amele'ctricf motor M a (Figure '2) which,whilesho'wn ior simplicity a's adjacent a single fan 3:1; in' pra'ctic:is preferablyrnounted outside the-oven housing; I I; driving thesh'a'ft 40 y of seveeral fans 31 mQunte'd -in' tandem; The fan 31 drawsin' air -tl'n'ou'ghtheintake port 32, causes itm tor-bexheatedasitrpa'sses the heat exchanger 34 and .discharges sit through thedischarge duct- 36 into the; upper: portion: of" the r oven housing I IvThe-thusrheated and' recirculated air passes: upwardain the directionof "the arrows,- and inthe opposite direction cto the directiomofntravel:of th conveyors I4; drying ztheworkpieces traveling;

3 downward on the shelves l8 of the work supports I6.

The heated air passes over the top of the upper baffle 29, and downwardon the other side thereof, still traveling in the opposite direction tothe direction of travel of the conveyor l4. The downwardly-traveling airpasses through the intake port 32 into the heating chamber 3| inresponse to the suction created by the fan 31 and is reheated as itpasses upward along the walls of the heat exchanger 34 whence it isagain drawn into the eye 39 of the fan 31 and discharged through thedischarge port 33 into the interior of the oven housing II. In thismanner the air passing through the interior of the oven housing I l isreheated and recirculated repeatedly.

In order to cool the workpieces on the-shelves [8 of the hangers [6 asthey near the unloading station adjacent the unloading opening l3, andalso to provide added fresh air to be mixed with the heated air withinthe housing ll, the latter above the unloading opening [3 is providedwith an air intake port 42 (Figure l) to which is connected an upwardlyinclined cool air intake duct 43. Mounted in the intake port 44 of theduct 43, as by the brackets 45, is an air intake fan 46 having blades 41mounted on a shaft 48 driven by an electric motor 49. The rotation ofthe fan blades 41 draws in fresh air from the outside of the ovenhousing H and forces it upward through the duct 43 and port 42, coolingthe articles on the shelves [8 as the latter near the unloading openingl3.

The housing ll above the intake port 42 is provided with a discharge orbleed-off port 50 to which is connected a bleed-off or discharge duct orstack 5i (Figure 1). A portion of the air forced into the housing llthrough the duct 43 by the fan is bled off or withdrawn through the portby the draft created by the stack 5! after it has cooled the articles onthe shelves I8. The remainder of the fresh air introduced by the fan 46passes upward and mixes with the heated air emerging from the heatingchamber discharge port 33, thus supplying a small portion of fresh airfor replenishing portions of heated air lost from the housing ll, suchas that which is exhausted by the fan described below.

In order to assist the downward travel of the heated air within thehousing H and to withdraw a portion of the heated air therefrom, thehousing It is provided with an outlet. 52 a short distance above theloading opening 12. Connected to the outlet 52 is the suction duct 53leading to the eye or intake port 54 of a suction fan or blower 55. Thelatter is provided with a shaft 56 carrying a rotor 51. The latter isprovided with the usual blades or vanes (not shown) and rotates within acasing or Volute 58, discharging the air through the discharge duct 59.

In the operation of the invention, a part of which has already beendescribed in connection with the description of the construction of theoven in, the fans 31, 46 and 55, and the conveyor [4 are started inoperation and the heat exchanger 34 is heated, such as by steam reachingit through the pipe 35. The shelves 18 of the hangers i6 are loadedthrough the loading opening l2 with the workpieces to be dried. Theseworkpieces may consist, for example, of sand cores, metal plates orother articles which require drying or which have been coated withvarious liquids such as paints, or inks. The workpieces efficient andeconomical manner.

on the shelves I8 pass upward adjacent the lefthand wall of the ovenhousing ll (Figure 1). As the articles pass upward, they encounter thedescending blasts of heated air which is being drawn downward by thecombined action of the fans 31 and 55. The articles on the shelves I8are thus dried and the drying action continues as they pass over theupper shaft 23 and travel downward until they arrive approximatelyopposite the upper bafile portion 28. Meanwhile the heated air in thehousing H is reheated and recirculated by the heat exchanger 34 and fan31 so that the workpieces are dried in a rapid, At this point theyencounter the upwardly-traveling blast of cool air introduced throughthe cool air duct 43 by the fan 46 and are thereby cooled sufficientlyto permit handling at the time they arrive opposite the unloadingopening [3. Here they are unloaded and the empty hangers l6 and shelvesl8 pass under the lower shaft 20 to reach the loading station. At theloading station, the shelves I8 are reloaded and the foregoing cycle isrepeated.

As previously stated, only a portion of the cool air introduced by thefan 46 is utilized to replenish the air drawn out of the housing H bythe fan 55, the remainder thereof being bled of! through the port 50 andstack 5! and discharged into the atmosphere. In this manner theworkpieces on the moving shelves I8 are subjected to a hot blast of airtraveling in the opposite direc tion, until they approach the unloadingstation, where a cool blast of air cools them for the remainder of theirtravel.

What I claim is:

1. A drying oven comprising an elongated vertical housing, a conveyormounted for travel along ascending and descending paths in said housing,air supply and exhaust fans connected to said housing, avertically-extending baflie structure dividing said housing verticallyinto conveyor-ascending and conveyor-descending chambers, said bafiiestructure having an air passageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers, a heat exchanger in said passageway, and a power-driven airrecirculation fan mounted adjacent one of said bafiie structure portsand arranged to draw air from the ascending chamber through saidpassageway past said heat exchanger into the descending chamber wherebyto recirculate and reheat the air in said housing.

2. A drying oven comprising an elongated vertical housing, a, conveyormounted for travel along ascending and descending paths in said housing,air supply and exhaust fans connected to said housing, avertically-extending bafile structure dividing said housing verticallyinto conveyor-ascending and conveyor-descending chambers, said bafliestructure having an air passageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers, a, heat exchanger in said passageway, and a power-driven airrecirculation fan mounted adjacent one of said bafi'le structure portsand arranged to draw air from the ascending chamber through saidpassageway past said heat exchanger into the descending chamber wherebyto recirculate and reheat the air in said housing, said air supply fandischarging cool air upward into said descending chamber near the bottomthereof for cooling the articles descending on said conveyor. and a coolair bleedoff duct opening out of said descending chamber above theconnection thereto of said air supply fan.

3. A drying oven comprising an elongated vertical housing, a conveyormounted for travel along ascending and descending paths in said housing,air supply and exhaust mechanisms connected to said housing, avertically-extending baflle structure dividing said housing verticallyinto conveyor-ascending and conveyor-descending chambers, said bafliestructure having an air passageway therethrough, a heat exchanger insaid passageway, and an air moving device connected to said passagewayto draw air from one chamber through said passageway past said heatexchanger into the other chamber whereby to recirculate and reheat theair'in said housing,

said air supply mechanism having a discharge duct inclined upward into"said housing and discharging cool air upward intosaid descendingchamber near the bottom thereof for cooling the articles descendingonsaid conveyor.

' 4. A drying oven comprising an elongated vertical housing, a conveyormounted for travel along ascending and descending paths in said housing,air supply and exhaust fans connected to said housing, avertically-extending baffle sageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers including an enclosure with a bottom inlet from said ascendingchamber and a top outlet into said descending chamber, a heat exchangerin said passageway, and a power-driven air recirculation fan mountedadjacent one of said bafile structure ports and arranged to draw airfrom the ascending chamher through said enclosure past said heatexchanger into the descending chamber whereby to recirculate and reheatthe air in said housin 7. A drying oven comprising an elongated verticalhousing, a conveyor mounted for travel along ascending and descendingpaths in said housing, air supply and exhaust fans connected to :saidhousing, a vertically-extending baflie structure dividing said housingvertically into structure dividing said housing vertically intoconveyor-ascending and conveyor-descending chambers, said bafflestructure having an air passageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers, a heat exchanger in said passageway, and a power-driven airrecirculation fan mounted adjacent one of said baffle structure portsand arranged to draw air from said ascending chamber through saidpassageway past said heat exchanger intosaid descending chamber wherebyto recirculate and reheat the air in said housing, said air supply fandischarging cool air upward into said descending chamber near the bottomthereof for cooling the articles descending on said conveyor.

5. A drying oven comprising an elongated vertical housing, a conveyormounted for travel along ascending and descending paths in said housing,air supply and exhaust fans connected to said housing, avertically-extending baflie structure dividing said housing verticallyinto conveyor ascending and conveyor descending chambers, said bafllestructure having an air passageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers, a heat exchanger in said passageway, a, power-driven airrecirculation fan mounted adjacent one of said tical housing, a conveyormounted for travelv along ascending and descending paths in saidhousing, air supplyand exhaust fans connected to said housing; avertically-extending"baflle structure dividingsaid housing verticallyinto conveyor ascending and conveyor descending chambers, said baillestructure having an air pas.-

conveyor ascending and conveyor descending chambers, said bafiiestructure having an air passageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers including an enclosure with a bottom inlet from said ascendingchamher and a top outlet into said descending chambar, a heat exchangerin said passageway, and a power-driven air recirculation fan mountedadjacent one of said baffle structure ports and arranged to draw airfrom the ascending chamber through said enclosure past said heatexchanger into the descending chamber whereby to recirculate and reheatthe air in said housing, said air supply fan discharging cool air upwardinto said descending chamber near the bottom thereof for cooling thearticles descending on said conveyor.

8. A drying oven comprising an elongated vertical housing, a conveyormounted for travel along ascending and descending paths in said housing,air supply and exhaust fans connected to said housing, avertically-extending baflle structure dividing said housing verticallyinto conveyor ascending and conveyor descending chambers, said bafflestructure having an air passageway therethrough with inlet and outletports communicating respectively with said ascending and descendingchambers including an enclosure with a bottom inlet from said ascendingchamber and a, top outlet into said descending chamber, a heatexchanger-in said passage- Way, a power-driven air recirculation fanmount 'ed adjacent one of said bafile} structure ports and arranged todraw air from the ascending cham her through said enclosure past saidheat exchanger into the descending chamber whereby to recirculate andreheattheniairin said housing, and a cool air bleed-off; ductopening outof said descending chamber ab'ove..;the connection there to of said airsupply fan.

A. FOX.

REFERENCES CITED The following references are of record in the

